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FrozenGate by Avery

A final answer: Do DX lasers have IR filters?

SMIDSY

SMIDSY

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Ok guys people ask it a lot ( I have twice) and I have received 2 different answers.

What I want to know is up to the 50mW green laser- do DX NEW WISH green lasers have IR filters that are acceptable.

Comment vote and poll please :)
 





The true DX50 and below usually always have IR filters. They aren't great, but they work well enough. There have been a few reports that a few don't have IR filters though. With the other models it is a gamble because nobody has reviewed them to know if they are consistent.
 
Well, i completelly took appart a mode hopping DX200, and observed something interesting.
There is no IR filter inside, and from the pictures or others taken appart, neither is there one in the DX100 and True DX100, but i think they don't need one.

People have measured low IR and thought it means a mediocre filter, but i believe the reason is somewhat different.


If i take a picture of the crystals, without the expander, i see a LOT of IR glow around the green beam. With the expander on, this glow decreases a little, at the collimator it decreases even more, and with the top on, the IR glow is gone.

I also noticed, that if i misalign the crystalls, the amount of the IR leaking increases, so i did this and again repeated the procedure. There was noticably more IR at the lower stages, but at the top, it was gone again.


So i believe, the reason for low IR leaking is this:

The IR isn't collimated, before it enters the crystals, but the green comes out very narrow.
The IR spreads out, when it leaves the crystals, and there is a narrow expander lens, which expands the green, and some IR, but blocks most of the IR.
At the collimator, there is again some IR blocked, and mostly only the green collimated.
At the top of the laser, the narrow apperture blocks even more IR.

At each of these stages, the amount of the IR decreases, and at the top, there is very little left.


Higher quality green lasers have a collimator between the pump diode and the crystal assembly (or at least a fast axis lens), and maybe this is the reason, they would leak more IR, if there wasn't a filter.


My thermopile hasn't arrived yet, but i haven't finished putting the laser back together, because i need the meter for final finetuning, so i will repeat this process in front of the thermopile, with a filter, that will only allow IR to pass.
 
Some do, some don't! As I've learned, the "True" or "New Wish" DO have an IR filter (in lieu of the "True" 100mW - does NOT have an IR filter). The 5mW module DOES have a filter. The 100mW - 200mW DO NOT have an IR filter.

NOW, these are facts based on MY EXPERIANCES with DX. However, because of their inconsistency, there is a huge chance that someone my object to my facts. I've ordered a "True" 30 before and know I got the regular 30, as if I wouldn't find out. >:( I know the difference because the chip is different, the brass fittings of the collimator lens are different, and the "True" or "New Wish" is better then other. The "True/New Wish" lasers are better collimated because the lens and crystals are of a better build design, the brass collimator is actually longer (you can also see the lens is closer to the aperture). You can see my reviews on DX to verify my "certified ownership".


Now I have a question to ask. How much, if at all, does it matter if DX have IR filters or not?
 
Some do and some don't. Really it all depends on the batch of lasers. Dx lasers aren't known for consistency.
 
im not sure this is the kind of thing we would vote on.. but w/e
i know my friends True DX30 had a IR filter but my flashlight styal and DX200 did not.
 
Cheers for the responses- its useful for people like me... we can now refer them to this thread for answers when people like bleating lambs keep asking 'IR filter?'

And the poll is here because the answer will be right in front of them in graph form! :)
 
So some lasers have been taken appart, and an IR filter found in them?

Also, isn't the DX200 also supposed to be from NewWish? Or is that just the "True" lasers?

DX says the 200 is also from NewWish..
 
FINAL BOTTOM LINE
The True 50 and below, TRUE SERIES ONLY, ALL have IR filters. DX claim they don't in case of freak units that don't. With others it depends on batch.
 
I just noticed, that my second DX200 has a lot of IR leaking out at the top. With the previous one it was hardly noticable at the apperture. Here, there is a huge white glow around the green beam. Still, not as much as at the collimator.

So it would seem it varies a lot even with the same type of laser.
 
Thanks guys again!

What I'll do is add an IR filter to the powerful lasers I get anyway (it cant do any harm) and that way I knwo for sure that there's one there :)
 
Good luck with your lasers!

I've only had bad luck with the powerfull ones so far.
 
cheers :)

Im going to close the poll in the next few days. Just to let all you people know :)
 
I do not think that any sweeping statements can be made regarding which DX units have or don't have IR filters.

DX seems to ship manyy variants of both true and non-true lasers. Some have filters and some don't. Unless you have access to all "True" and "Non-True" units that DX has shipped, you will never know for sure. So, if there's concern - verify the unit in question and then you can be only be sure about that unit only.
 
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